A number of systems and programs are offered on the market for the design, the engineering and the manufacturing of objects. CAD is an acronym for Computer-Aided Design, e.g. it relates to software solutions for designing an object. CAE is an acronym for Computer-Aided Engineering, e.g. it relates to software solutions for simulating the physical behavior of a future product. CAM is an acronym for Computer-Aided Manufacturing, e.g. it relates to software solutions for defining manufacturing processes and operations. In such systems, the graphical user interface (GUI) plays an important role as regards the efficiency of the technique. These techniques may be embedded within Product Lifecycle Management (PLM) systems. PLM refers to a business strategy that helps companies to share product data, apply common processes, and leverage corporate knowledge for the development of products from conception to the end of their life, across the concept of extended enterprise.
The PLM solutions provided by Dassault Systèmes (under the trademarks CATIA, ENOVIA and DELMIA) provide an Engineering Hub, which organizes product engineering knowledge, a Manufacturing Hub, which manages manufacturing engineering knowledge, and an Enterprise Hub which enables enterprise integrations and connections into both the Engineering and Manufacturing Hubs. All together the system delivers an open object model linking products, processes, resources to enable dynamic, knowledge-based product creation and decision support that drives optimized product definition, manufacturing preparation, production and service.
Some CAD systems now allow the user to design a 3D modeled object based on a set of two-dimensional (2D) pictures, for example photos, of a real object that is to be modeled. Existing methods include providing to the system several overlapping pictures representing the real object from different angles. Then, the user is involved to match up identical points, lines and edges across the pictures. Optionally, the user adds curves on pictures, while maintaining the overlapping coherence. The next step is for the system to automatically compute a 3D version of the object. The geometry of this object is a set of 3D points, curves and lines representing characteristic edges. It may be wireframe geometry. Optionally, the user adds 3D curves on this wireframe geometry. The user is involved again to create surfaces bounded by the curves computed at previous steps. Boundary curves of each surface are selected by the user. Depending on the application, a wireframe model, a surface model or even a solid model might be created from the initial pictures, although this is not perfectly clear from prior art literature.
As can be seen, this prior art involves the user during two steps. The first step is to set up the matching across overlapping pictures. This step seems to be unavoidable. After the system has created 3D curves, the other step is for the user to select boundary curves in order for the system to create surfaces. This manual selection is required because the systems of the prior art are unable to automatically create surfaces from 3D curves. This manual process can be very long and tedious from the user point of view. Furthermore, an incorrect selection results in twisted or overlapping surfaces. Identifying and repairing these pathological surfaces is the user's responsibility, which lengthens again the path to the virtual 3D object.
Thus, the invention aims at improving the design of 3D modeled objects based on 2D views.